mineral

Pink corundum (ruby-bearing corundum)

Corundum, Al₂O₃; red varieties are ruby, while pink material is commonly termed pink sapphire

AI-generated identification · may be incorrect

Hardness 9 Mohs; vivid pink-red color, vitreous to greasy luster, trigonal crystal structure, and poor basal cleavage with conchoidal or uneven fracture. The specimen appears massive and heavily fractured, with pale matrix inclusions.

Identified September 18, 2026More mineral →

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At a glance

Common name: Pink corundum (ruby-bearing corundum)
Scientific name: Corundum, Al₂O₃; red varieties are ruby, while pink material is commonly termed pink sapphire
Category: mineral
Identified: September 18, 2026
Method: Standard

AI Estimated Value

About $20-$100 for an opaque matrix specimen; $100-$1,000+ for attractive natural crystals, with transparent gem-quality ruby or sapphire potentially worth thousands per carat.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms through high-grade metamorphism or aluminum-rich igneous processes, commonly in marble, gneiss, or basalt-related deposits. Individual crystals may be Precambrian to younger, depending on locality.

Uses & applications

Gem-quality transparent material is cut as ruby or pink sapphire; opaque specimens are mainly collector pieces or abrasive sources. Corundum is also used industrially for abrasives and refractory ceramics.

Geological facts

Ruby’s red color is caused mainly by chromium, whereas pink corundum may contain lower chromium concentrations. Corundum is second only to diamond in natural mineral hardness.

Field identification & locations

Identify by exceptional hardness, strong color, nonmetallic luster, and lack of prominent cleavage; ruby commonly fluoresces red under long-wave UV. Important localities include Myanmar, Sri Lanka, Madagascar, Mozambique, and India.